Network I/O and streaming in D2

[Andrei Alexandrescu]

Walter Bright wrote:
> Adam Ruppe wrote:
>> My network thing is very simple: it opens a socket, then wraps it up
>> in a File struct, via FILE*. Then, you can treat it the same way.
> 
> That's the traditional way to do it, but I'm not so sure it's the right 
> way for the future. Wouldn't it be better to have an interface to it 
> that is a range, rather than pretend it's a FILE* ?

I initially also thought that a file (or socket etc.) should be a range, 
but then I realized that that would overload roles. It's best to have a 
handle/ranges architecture in which the handle (e.g. File) is 
responsible for opening, closing, and managing the connection, and 
several ranges are responsible for fetching data in various ways (by 
character, by chunk, by line etc.)

BTW I'm virtually done implemented readf. I only need to parse 
floating-point numbers and strtod won't work. Walter, could you please 
email me your strtod implementation? Thanks.

The current issue with readf (and other similar formatted read routines) 
is that they require a primitive peek() that looks up the current 
character in a stream without swallowing it. This is not a FILE* 
primitive, but can be simulated (slow) by using getc() and ungetc(). 
Fortunately on GNU's I/O libs peek() is easy to define (actually they 
have an internal routine by that name), and on Windows dmd uses Walter's 
I/O library, which again has fast peek().


Andrei